Counterbalancing device



April 24, 1934. R R BL S ET AL 1,956,341

COUNTERBALANCING DEVICE Original Filed April 14, 1928 3 Sheets-Sheet l v l7 VINVENTOIZS April 24, 1934. R. R. BLOSS ET AL COUNTERBALANCING DEVICE Original Filed April 14, 1928 3 Sheets-Sheet 2 P 1934- I R. R. BLOSS ET AL 1,956,341

COUNTERBALANCING DEVICE Original Filed April 14, 1928 5 Sheets-Sheet 3 INVENTOPS Pic/laid E. 31055. Pay C PfezY,

- A TTORNEY Patented Apr. 24, 1934 UNITED STA 1,956,341 COUNTERBALANCING DEVICE Richard R. Bloss and Roy 0. Pfeil, Columbus,

Ohio, assignors, by mesne assignments, to International Stacey Corporation, Columbus,

Ohio, a corporation of Ohio Original application April 14, 1928, Serial No.- 270,071. Divided and this application June 7,

1929, Serial No. 369,203

'7 Claims.

Our invention relates to a counterbalancing device. It relates particularly to a counterbalancing device that is attached to and operated in conjunction with the crank of an oil well drilling and pumping mechanism.

Previous counterbalances, in most instances, have been attached to and have operated in con- Junction with either the band wheel or walking beam and such counterbalances have not been 1.) entirely satisfactory for various reasons. It is one object of this invention not only to provide a counterbalance which is adapted to be attached to and operate in conjunction with the crank of an oil well drilling and pumping mechanism but to provide a counterbalance which is so designed and constructed as to be adapted to any standard make of crank which may already be in use in the field.

Some advantages of a counterbalance which 2:) is so designed as to be attached to and operate with the crank reside in the fact that the wear and tear on the band wheel and. walking beam and the torsional stress on the crank shaft, as produced by ordinary types of band wheel or :3 walking beam counterbalances, are eliminated.

With our design and construction, we avoid unusual stress on any part of the drilling and pumping mechanism with the exception of the crank arm itself.

Other advantages of our invention reside in the fact that our counterbalance is located outside of the rig house whereby it may be readily adjusted and operated. It is so constructed that it may be easily shifted in an arcuate path 'with relation to the crank arm so as to synchronize the counterbalance effect with the load.

In our invention, features of adjustability have been provided in order to meet the variations in weight ofthe suspended pumping and drilling mechanism and the oil or other fluid above the plunger. Also, we have provided features of adjustability which will enable us to synchronize the counterbalance effect with the sucker rod pull.

This application is a continuation in part of our application Serial No. 167,924 filed February 14, 1927 and is a division of our application Serial No. 270.071 filed April 14, 1928.

Other advantageous features will appear from the following detailed description and the preferred embodiment of our invention may be seen in the accompanying drawings wherein similar characters of reference designate corresponding 7 parts and wherein: v

Figure 1 is a perspective view of the preferred embodiment of our invention and showing it mounted upon a crank.

Figure 2 is a sectional. view taken on the line 2-2 of Figure 3.

Figure 3 is a front elevation of the structure shown in Figure 1.

Figure 4 is a sectional view taken on the line 4-4 of Figure 3.

Figure 5 is a front elevation of a modified form of ourinvention.

Figure 6 is a side view, partly in section, of the device shown in Figure 5.

Figure '7 is a front elevation of another modified form of our invention.

Figure 8 is a side view, partly in section, of the device shown in Figure 7.

Figure 9 is a front elevation of still another modified form of our invention.

Figure 10 is'a side view, partly in section, of th device shown in Figure 9.

Figure 11 is a sectional view taken on the line 7'7 of Figure 9.

' Figure 12 is a frontelevation of still another modified form of our invention.

Figure 13 is a side view, partly in section, of the device shown in Figure 12.

Referring to the drawings, we have shown a crank 1, which may be of any standard make, mounted on and keyed to a crank-shaft 2. The crank-shaft 2 operates in a bearing 3 that may be supported by a jack-post or a similar supporting structure. A counterbalance unit 4 is suspended from the hub of the crank 1 by means of a cap 5, as shown in Figure 2, which cap straddles the top of the crank 1 to prevent movement of the counterbalance unit along the crank shaft 2 andrelative to the crank. The upper part of the crank acts as a shoulder which fits in a socket in the cap 5.

We have provided means for drawing the main body portion of the counterbalance unit 4 towards the cap 5 or releasing the main body portion so that it may be moved away from the cap. This is accomplished by providing rods 6, whose outer ends are attached by clevises to the main body portion of the counterbalance unit as shown at '7 in Figures 1 and 3.

The cap 5 is provided with tubular housings 8 and one of these housings has a longitudinal cutaway portion or slot 8. The rods 6 may be moved into cooperative relation with the cap 5 by inserting one of the rods endwise into one hollow tubular, portion 8 of the cap 5 and through the slot 8' of the other. Lugs 9 may be provided on the cap 5 to prevent the rods from easily becoming disengaged therefrom. It will be apparent that,

by tightening the nuts 10 on the rods 6, the main body portion of the counterbalance unit may be moved towards the hub of the crank 1, and that by loosening these nuts it may be allowed to move away from the said hub.

In the lower part of the counterbalance unit 4 we have provided a plurality of holes 11 as a means whereby supplemental weight elements 12 may be attached to or detached from the counterbalance unit. These supplemental weight elements 12 may be attached to the counterbalance unit in any desired number by means of bolts 13. It will be understood that a pitman of any preferred form may be attached to the crank 1 by means of the wrist pin 14. A plurality of holes 15 are provided in the crank 1 to permit adjustment of the wrist pin to difierent positions along the length of the crank and forother reasons hereinafter described.

The counterbalance unit 4 is provided with a plurality of lugs 16 that are movable on bases 17 which are disposed in an arcuate path on the surface of the counterbalance unit and held on the counterbalance unit by bolts 17'. These lugs. provide a means for adjusting the weight center of the counterbalance unit to a multiplicity of positions with respect to the crank arm 1. Such counterbalance unit is also provided with openings 18 which are adapted to receive one end of the wrist pin 14 and with slots 19 which are adapted to receive a bolt 20 that extends through the crank 1 and the counterbalance unit.

In the assembling of our device, the counterbalance unit is placed in a position with relation to the crank 1 whereby the cap 5 may be placed over the crank hub and the top of the crank 1. At this time one of the rods 6 is already in position in its tubular housing 8 and the other of these rods 6 is thereupon moved into cooperative relation with the cap 5 by way of the slot 8. The lugs 16 are then moved to a position proximating to the ones shown in Figures 1 and 3 wherein the lower end of the crank 1 is positioned between two of the lugs 16. At this time, the nuts 10 on the rods 6 are tightened to draw the main body portion of the counterbalance unit upwardly until the crank 1 is wedged tightly between the lugs 16 and the cap 5. Then, the bolt 20 is inserted through one of the wrist pin holes 15 of the crank and then through one of the slots 19 in the counterbalance unit. Our device may be disassembled from the crank by reversing the order of operations hereinbefore et out.

In Figures 5 to 13 inclusive, we have shown various modifications of our invention. For instance, in Figures 5 and 6 we have shown one modified form of our invention in which a counterbalance unit 21 is preferably mounted on the hub of a crank arm 22 that has been machined slightly.

This counterbalance unit 21 is mounted between the crank arm 22 and the jack-post or similar supporting structure 23 on which a bearing 24 is mounted as a means for supporting a crankshaft 25. A semi-circular clamp 26 cooperates with a semi-circular recessed portion 27 in the counterbalance unit to hold the counterbalance unit on the hub of the crank 22. The counterbalance unit is provided with a plurality of tapered sockets 28 which are designed to cooperate with a tapered boss 29 mounted on a plate 30 that extends laterally from the crank 22. Such plate 30 may be welded or otherwise attached to any standard type of crank and may extend from the crank at any desired location.

The tapered boss and tapered sockets provide a means for adjusting the weight center of the counterbalance unit to a multiplicity of positions with respect to the crank arm 22 and a bolt 31 is provided for holding the crank arm 22 and the counterbalance unit 21 in their respective adjusted positions. When the crank arm and counterbalance unit are in cooperative relation, the bolt 31 extends through the tapered boss 29 and through holes in the base of the tapered socket 28.

As in the preferred form of our invention, we have provided a plurality of bolt holes in the lower part of the counterbalance unit 21 as a means whereby supplemental weight elements 32 may be attached to or detached from the counterbalance unit as desired. A wrist pin 33 is also provided as a means whereby a pitman may be attached to the crank arm and a plurality of holes 34 are provided in the crank arm to permit adjustment of the wrist pin to different positions along the length thereof.

It will be apparent that the counterbalance unit 21 may be readily attached to or detached from the crank arm. In order to attach the counterbalance unit to the crank arm it is only necessary to mount the unit on the hub of the crank and then insert the bolt 31 through the tapered boss 29 and through the hole in the base of one of the tapered sockets 28. The counterbalance unit may be easily detached from the crank arm by reversing the order of operations just described.

Referring to Figures 5 and 6 of the drawings, it will be seen that the counterbalance weight structure is movable along the hub of the crank arm either toward or from the inner face of this crank arm. In order that the counterbalance weight structure may be effectively maintained in such spaced relation to the crank arm that the crank arm will be free to move in a rotary path without interference from the counterbalance weight structure, we have provided a pivoted latch 34' which is normally ineffective when the counterweight structure is operatively connected to the crank arm. This pivoted latch may be swung downwardy to such extent that one end thereof will be between the semi-circular clamp 26 of the counterweight structure and the crank 22 to hold the counterweight structure in spaced relation to the crank arm.

Referring to Figures 7 and 8 of the drawings, we have shown another modified form of our invention which consists of a counterweight structure 35 that is of substantially the same construction as the counterweight structure shown in Figures 5 and 6, with the exception that the counterweight structure 35 is mounted on the crank shaft 38 and is provided with a plurality of radial slots 36. To attach the counterweight structure shown in these figures to the crank arm 37 it is only necessary to mount the counterweight structure on the crank shaft 38 and then insert a bolt 39 through one of the wrist pin holes 40 and through one of the radial slots 36. A small block 41 that fits within the radial slots and has a surface which bears against the inner face of the crank arm 37 is provided to maintain the counterweight structure in proper spaced relation to the crank arm.

It will be apparent that the weight center of the counterweight structure 35 may be adjusted to a multiplicity of positions with respect to the crank arm 37 by laterally swinging the counterweight structure and the crank arm relative to each other until the wrist pin holes in the crank arm are complemented to the desired radial slot 36 in the counterweight structure. Also, it will be understood that a plurality of bolts 39 may be used to operatively connect the counterweight structure with the crank arm and that the radial slots 36 are of such nature that the counterweight structure may be adjusted radially with respect to the hub of the crank arm 37.

In Figures 9 and 10, we have shown still another modification of our invention which is an exact duplicate in construction to the device shown in Figures 7' and 8, with the exception of the means provided for operatively connecting the counterweight-structure and the crank arm. As shown in these figures, a counterweight structure 42 is mounted on the crank shaft.

The counterweight structure 42 and the crank arm 43 are operatively connected together by means of Ushapcd clevises 45 which are attached to the crank arm 43 by means of a bolt 46 which extends through one of the wrist pin holes of the crank arm and through the ends of the clevises 45, as shown in Figure 11. Each U- silapod clevise forms a part of a connecting link 4'7, which connecting link is attached at one end thereof to one of a plurality of tapered bosses 44 that are disposed in an arcuate path on the face of the counterbalance. Turnbuckles 48 are provided in each of the connecting links so that the connecting links may be lengthened or shortened as desired. By varying the point of connection between the connecting link and the counterweight and by adjusting the respective turnbuekles 48, the center of weight of the counterweight structure may be adjusted to a plurality of positions with respect to the crank arm. It will be apparent that this counterweight structure may be attached to any standard make of crank.

In Figures 12 and 13, we have shown another modified form of our invention which consists of a counterweight structure 49 that is of substantially the same construction as the counterweight structure shown in Figures 9 and 10. This counterweight structure is mounted on the crank-shaft of an oil well drilling or pumping mechanism as shown in Figure 13 and is provided with a plurality of radial slots 50. The counterweight structure 49 may be attached to the crank arm 51 by inserting bolts 52 and the wrist pin through the wrist pin holes of the crank arm, both being then passed through one of the radial slots 50. In these figures, we have shown a counterweight structure in which supplemental weight elements 53 may be inserted to vary the mass of weight of the counterweight structure and have provided bolts 54 that are adapted to extend upwardly through the counterweight structure and the supplemental weight element 53 to hold the weight element in position. It will be apparent that this counterweight structure is adapted for use with any standard rig and that the center of weight of the counterweight unit may be adjusted to a multiplicity of positions with respect to the crank arm by varying the slot through which the bolts 52 extend.

Referring to the drawings, it will be seen that we have provided a means whereby the counterweight structure may be detached from the crankshaft or crank hub on which it is mounted and such crank-shaft or crank hub relieved of the weight thereof. Further, we have provided a means for maintaining the counterweight structure in such position with relation to the crank hub and crank-shaft that it may be quickly and easily remounted on the crank hub or crank-shaft after it has once been detached therefrom.

In order to provide a means whereby this may be accomplished, a shelf 55 or other supporting structure is provided immediately below the counterweight structure. This bracket is intended to receive and support the counterweight structure when the nuts 56 on the bolts 57, which are made of extra length for this purpose, are sufliciently loosened to permit the counterweight structure to be practically entirely disconnected from the crank hub or crank-shaft. At the same time, the counterweight structure is maintained in'such position that it may be quickly and easily remounted on the crank hub or crank-shaft by the simple expedient of tightening the nuts on the bolts 5'7 to such an extent as to draw the counterweight structure upwardly to its operative position.

From the foregoing description and the drawings, it will be clearly seen that we have provided a counterweight structure which may be attached to any standard make of crank and which is ad-' justable to permit any desired counterbalancing effect to be obtained. The desired counterbalancing effect may be obtained in several ways, the most simple of which is by adjusting the counterweight structure and the crank arm laterally with relation to each other until the center of weight of the counterweight structure is in the desired position with relation to such crank arm. Another means of obtaining the desired, counterbalancing effect is to vary the number of supple-- m'ntal wright elements on the counterbalance unit. Still another means is by adjusting the pitman of the drilling and pumping mechanism to various positions along the crank arm by varying the position of the wrist pin on the crank arm. From the above it is apparent that our counterweight structure may be quickly and easily shifted with relation to the crank arm to synchronize the counterbalanceeffect with the load.

It will also be apparent that by providing the counterweight structure which is so designed as to be attached to any standard make of crank, we have provided an economical and effective means for counterbalancing the movements of various parts of oil well drilling and pumping mechanism that has decided advantages over a band wheel or walking beam counterbalance.

Another advantage resides in the fact that the IOU strain on the band wheel and the torsional stress on the crankshaft, as produced by band wheel and Walking beam counterbalances, are eliminated. In our device, we have connected the weight directly to the crank arm, which practically eliminates any stress on the band wheel,

keys, crank-shaft and associated parts.

A further advantage resides in the fact that our counterweight is so constructed, and attached to the crank arm in such a manner that the counterweight is at a maximum distance from the center of the crank-shaft. Obviously, the further the counterweight is removed from the crankshaft the less weight is required. Our device will and a slot in one of said housings, and a plurality of rods having one of their ends mounted in each housing and having their opposite ends connected to said weight structure.

2. An attachment for the crank arm of an oil well drilling or pumping mechanism comprising a weight structure, means for mounting said weight structure on said crank arm, said means embodying a cap having tubular housings thereon and rods connected to said weight structure and adapted to extend through said housings.

v3. An attachment for the crank arm of an oil, gas or artesian well drilling or pumping mechanism comprising a weight having a plurality of lugs disposed along an arcuate line, said lugs being adapted to engage said crank arm.

4. An attachment for the crank arm of an oil well drilling or pumping mechanism comprising a Weight structure, means for attaching said weight structure to said crank arm, said means comprising a plurality of lugs on said weight structure adapted to engage said crank arm, and a plurality of radial slots in said weight structure adapted to be brought into alignment with openings in said crank arm.

5. An attachment for the crank arm of an oil well drilling or pumping mechanism comprising a weight structure, means for attaching said weight structure to said crank arm, said means comprising a plurality of lugs on said weight structure adapted to engage said crank arm, a plurality of radial slots in said weight structure and adapted to be brought into alignment with openings in said crank arm, a cap having tubular housings therein, and a plurality of rods'having one of their ends mounted in said tubular housings and their. opposite ends connected to said weight structure.

6..An attachment for the crank arm of oil well drilling or pumping mechanism comprising a weight structure, means on said structure for fitting over the outer end of said crank arm, a cap having tubular housings therein, and a plurality of rods having one of their ends mounted in said housings and their opposite ends connected to said weight structure.

7. In combination with a crank arm havin a plurality of openings and a crank shaft of an oil well drilling or pumping mechanism, a weight structure, means connecting the weight structure to the crank arm, said means comprising a plurality of radial slots spaced laterally from each other in said weight structure and each of which may be brought into alignment with an opening in said crank arm and a member extending through one of said slots and said opening when they are in alignment, and means including a cap member attached to said weight structure and supported by said crank arm for moving said weight structure radially along said crank arm without removing said member from the-aligned opening and slot in said crank arm and said weight structure, respectively, said last-named means being independent of said connecting means.

RICHARD R. 'BLOSS.

ROY C. PFEIL. 

